You can listen to this 12-parter teaching on the Four Dharma Seals by His Holiness Karmapa at this web-link… http://www.youtube.com/watch?v=Vx-VfQKuxAE
The four Dharma seals are:
All compounded phenomena are impermanent, everything defiled (with ego-clinging) is suffering, all phenomena are empty and devoid of a self-entity, and nirvana is perfect peace.
Karmapa talks about some ways in which we go wrong in our practice and what is the true essence of Buddhism. It is important to have a deep insight into these four seals at least intellectually to know how to approach/practice Buddhism… everything in Buddhism on the path can be traced back to these four seals… that’s why they are called ‘seals’.
I really deeply recommend all readers to study this topic deeply, not only through this video but also through your own contemplation and relating it to your own practice. I found this understanding profoundly reshaping my practice and my whole life and it continues to be so further more….